My sister's '92 240(manual transmission) is in need of new shifter bushings(which I have). My question is, how does one go about installing them, and is this something a home mechanic can do? Thank you and have a splendid holiday :)

Yes, a home mechanic can do it, but it involves a combination of manual dexterity and brute force... Remove the shifter boot. You'll see a circlip over a rubber ring, over a nylon ring, which all presses down on the top half of the ball at the base of the shifter. Don't take it out yet. Place a crescent wrench under the shifter knob & tap it with a hammer to knock the shifter knob off. Now crawl under the car (jackstands really help!) and where the shifter ends, and intersects the shift rod fork, you'll see a hateful little 4mm (could be 3mm, don't recall for sure) allen screw recessed into the bottom of the shifter. Hammer a GOOD QUALITY allen key into it. Cheap tools will round out those small allen bolts & make life positively miserable. Remove that screw, and drive out the rod that passes through the fork & shifter. Now remove the circlip from above, and everything lifts apart. Assembly is the opposite of removal...

-Chris